An administrator is looking to apply a new service pack for an OS on several systems that run business critical applications for a large international finance corporation.  Which of the following should the administrator do FIRST？（）

• A、 Deploy the service pack to a single department within the corporation. 
• B、 Upgrade the system with requirements for that service pack. 
• C、 Deploy the service pack to a non-critical application server. 
• D、 Submit a change control for the service pack deployment.